CFD for HVAC applications

Ventilation Openings / DIN 18232

The aerodynamics of ventilation openings and regulating mechanisms is crucial for safety in Buildings in case of fire.

DIN 18232 specifies how the aerodynamics of such devices is to be measured and calculated. CFD simulations confirm to
the DIN regulations and deliver the same results of wind tunnels at less cost.

Courtesy of Firma AeroTec Europa GmbH

Air Conditioning of a Theatre

The theatre's geometry is shown in the first picture. The heat sources considered include the light and people heat
loads. They are distributed in the model accordingly.

The thermal comfort condition is defined to be below 26°C. The ventilation and air conditioning systems should therefore
guarantee a maximum temperature of 26°C.

The operation conditions of one of the proposed systems are shown in the second picture. The isosurface corresponds to
a temperature of 30°C. The volume within the isosurface has even higher temperatures. It can be seen that a large
segment of the upper rows will be subjected to very high temperatures. This system is hence not adequate.

Courtesy of EBF GmbH.

Smoke Distribution in Case of Fire

The animation summarizes the results of an investigation dedicated to predict the time people would have to evacuate
a multi-story building in case of fire.

Assuming that the flames start in a room at a lower floor, the atrium is filled fairly quickly with smoke. The smoke
concentration in the vicinity of the balconies is higher than 10%.

The time during which the escape routes remain free of such high concentration was predicted to be long
enough to ensure a reasonable evacuation time.